Re-sync topology upon PUBSUB connection

scottgeary commented 8 years ago

As soon as we make a PUB/SUB connection, we should retrieve the current topology, to ensure the flipper_client is up-to-date.

If for any reason we loose connectivity (such as a detectable TCP failure), this ensures any missed +switch-master events can be mitigated.

This works by

creating a new channel between the Manager <= Monitor.
firing a ConnectionEvent upon confirmation of SUBSCRIBE +switch-master
The Manger will then fetch the current topology
Inject MasterSwitchedEvent into the unthrottled connectionChannel

This means we can also remove the startup intiliseTopology(), as we know that same kind of event will take place upon any sentinel connection now.

The various flapper_clients will likely start to receive more events (depending on your Cluster + Sentinel count), but being consistent and reliable is the key here.

scottgeary commented 8 years ago

Looks like the Travis build did complete, but it couldn't talk to "Coveralls":

Bad response status from coveralls: 422 - {"message":"Couldn't find a repository matching this job.","error":true}

mdevilliers commented 8 years ago

I've restarted the build - will check back later

mdevilliers commented 8 years ago

Great work

mdevilliers / redishappy

Re-sync topology upon PUBSUB connection #42